Art of manufacturing lubricating oils



Patented Feb. 8, 1944 ART or MANUFACT URING LUBRICATING OIS Eugene Lieber, West New Brighton, N. Y., assignor to Standard Oil Development Company, a

corporation of Delaware No Drawing. Application November 8, .1941, Serial No. 418,325

13 Claims.

The present invention relates to the art of manufacturing lubricating oils, and more specifically to addition agents capable of reducing the pour points of waxy lubricating oils, and to waxy lubricating Oils containing such addition agents. The invention will be fully understood from the following description.

Addition agents for lubricating oils have been made by condensation of chlorides of long chain fatty acids with aromatic hydrocarbons in the presence of relatively large amounts of aluminum chloride. These materials which are described as aryl alkyl ketones-have been proposed as agents for increasing the oiliness and adherence of oils to bearing surfaces. Examination of a large number of these compounds shows that many of them have little or no wax-modifying qualities and in consequence are of small effect in reducing the pour point of waxy lubricating oils.

The present invention-relates to a method-for greatly increasing the pour-depressing potency of these aryl alkyl ketones and comprises a process in which the said ketones are recondensed with shortchain dihalo compounds. The short chain compounds which are used in this connection are preferably halogenated hydrocarbons containing from 1 to 5 carbon atoms, such as dichlor methane, ethylene dichloride, propylene dichloride and the like, as well as the corresponding bromine, fluorine and iodine compounds. Among the various compounds that can be used, the chlorine derivatives are the cheapest, the most readily available and give the most satisfactory products, and among these ethylene dichloride is to be preferred.

The aryl alkyl ketones employed as the other reactant in the present process are characterized by the following structural formula:

where R is a cyclic radical and R is an aliphatic heterocyclic radicals such as furfuryl, furyl, carbazyl and thelike, as wellas the radicals of furan, pyrrole, thiophene, pyridine, etc. It will be understood that any of these radicals may be em--' ployed in the ketone in which the other radical is a hydrocarbon group of at least six carbon atoms. Substituted aromatics or other cycle com-- pounds may be used containing oxygen, nitrogen, or other inorganic element in the substituent group, as for example, hydroxy aromatic compounds, e. g., phenol, alphaor beta-naphthol, cresols, petroleum phenols, especially the fraction thereof having an average composition corresponding to tertiary butyl benzene, or amino aro-' matic compounds, e. g., aniline, toluidine, naphthylamine, etc. The aliphatic radicals are preferably saturated such as hexyl, heptyl, octyl, nonyland higher such as heptadecyl, but unsatu rated open chain aliphatic radicals may also be employed as well as aliphatic cyclic radicals such as found in the naphthenic acid and alcohols.

In the condensation, the two reactants are ordinarily used in about equal weight and are mixed with or without a solvent such asnaphtha, kerosene or an inert halogenated solvent such as tri or tetrachlor ethane, carbon disulflde or the like, The condensation is effected by the use of catalysts such as aluminum chloride, boron fluoride and their known equivalents. The catalyst is preferably added to the mixture of the two re-f actants and while the proportionmay vary, itis found that as little as .10 mol catalyst per mol of the dihalo compound is satisfactory. The temperature may vary over aconsiderable range, for example, from about room temperature up to about 150 F.,butit is preferred'to use a temperature from about room temperature to or F. The ingredients should be stirred during the reaction during whichlarge volumes of hy drogen chloride gas are evolved. Ordinarily an hour or two is satisfactory for the reaction}, but the various factors of time, temperature, catalyst and the amount thereof are not totally independent so that one or more may be varied over a rather wide range if compensation is made in other factors. The product is recoyered from the reaction mixture by first diluting 'with alargevolume of solvent such as kerosene or naphtha and hydrolyzing the catalyst with water or alcohol, but preferably, with a mixture of water and "alcohol whichsettles as'a' layer fromthe' oil and contains the hydrolyzedproducts of the catalyst. The oily material is, withdrawn and sub ected to: distillation up to a temperature around i 600 F which effects the. removal of the solvent and lower boiling products which are not very effective from the wax modifying standpoint and the desired product is collected as the distillation residue.

The product is a viscous, green to brown oil; the color is. good and while it may darken light oils to some extent," it is a satisfactory shade, characteristic of high grade petroleum oils. When this material is added to a waxy lubricating oil in proportion of /2 to 5%, a marked depression in the pour point is obtained. The exact amount of the material to be added depends on the particular ketone and dihalo aliphatic compound em- 1 ployed in the manufacture, and likewise on the particular oil in which the material is used, as well as the degree of pour depression desired. The product may also be employed as a dewaxing aid in about the same amounts disclosed above and as an ingredient in various compositions containing wax where it is desired to modify the crystal. structure. I

Although the products of this invention are apparently complex and'composed of a mixture of compounds at least having some difference in molecular weight, if not in actual type of structure, it is believed that the majority of the components of this product are linear condensation products having a general formula in which R represents an aromatic or other cyclic radical, R is a monovalent aliphatic radical such as an alkyl group containing at least 6 carbon atoms, R" is a bivalent hydrocarbon interlinking group having from 1 to 5 carbon atoms and n is an integer indicatin the number of monomeric units combined linearly, between the ter- 'minal units shown. If a phenolic ketone is used as raw material, then the linear condensation product will contain hydroxy groups, which might be represented in the above general formula as being attached directly above each R.

' Such phenolic condensation products can be converted to corresponding metal derivatives, e. g., of calcium, barium, magnesium, aluminum or sodium, in the same way in which simple phenols are converted into corresponding metal phenates, and such metal phenolic condensation products may be used as addition agents in lubricating oils or other petroleum fractions. The phenolic condensation products can also be used as intermediates for conversion into other types of products useful in the industrial arts; for instance, they may be reacted with sulfur halides to form high molecular weight phenolic sulfur-containing con- ','densation products useful as anti-oxidants in mineral lubricating oils and other petroleum hydrocarbon fractions. .Also, if desired, the hydroxy groups of the phenolic condensation prod- ,ucts may be esterified to form a new type of high molecular weight polyesters, useful as addition agents in lubricating oils a well as in fatty oil compositions to be used in making paints, varnishes, and other coating or impregnating compositions.

' Example I A series of heptadecyl arylketones were made up according to the following procedure. One molecular proportion of stearic acid was converted to the acid chloride by reacting with phosphorus trichloride on a Water bath and the stearyl chloride was 'decanted from the aqueous phosperature was maintained for about 5 hours. The

reaction mixture was cooled, diluted with an equal volume of, kerosene and neutralized with alcohol and water. The sludge was settled and the kerosene-layendistilled to 600 F. with fire and steam. These three ketones were then added to a waxy oil and the pour point determined.

Pour point Sample 1% ketqne k e t ozie r. 9F. I. 0il+Phenyl-heptadecyl ketone 30 15 Oil+Naphthyl-heptadecyl ketone 30 20 01l+Xylyl-heptadecyl ketone 30 20 From the above it will be seen that the ketones were very weak pour point depressants.

Example I I I,

The three ketones prepared in Example I were then recondensed with ethylene dichloride using equal weights and14 grams of A1013 per grams of the ketone. Condensation was effected by refluxing for 3 hours then diluting with kerosene, neutralizing with alcohol and water, decanting the kerosene layer and distilling to 600 to secure the desired product as a distillation residue. The yield of product varied from 77% to 88% based on the weight of ketone used and the product was a dark green, viscous oil. I

These three products were then added to a waxy oil of 30 F. pour point with the following Example III I f Phenyl heptadecyl ketone was recondensed with ethylene dichloride as in the previous example except that the proportion of catalyst was varied. Thepour depressor was again tested in the 30 F. pour point oil;

, Pour point Yield/100' gr. ketone Gr. catalyst/100 gr. ketone It will be seen that if mo re 'than" 7 gramsiof catalyst is used the pourpoint depressor isiin dependent of the amount used;

Phenyl" hept'adecyl ketone was. recondensed with an equal quantity of ethylene dichloride as before using '7 grams of catalyst per 100 grams of ketone but providing time'of 8 hours refluxing instead of 3 hours as before. The pour depressing power was somewhat increasedby the. lesser time.

Ewample V I-Ieptadecyl naphthyl ketone was prepared as in Example I and was recondensed with an equal amount of ethylene dichloride using A1C13 and a reaction period of 8 hours. The product was recovered as before and 1% of the product in the 30 F. pour point oil reduced the same to -20 F.

Example VI A phenyl-aliphatic ketone was made upby condensation of benzol with acid chlorides of mixed acids prepared by the low temperature oxidation of parafi'in wax, the waxy acids being a out having an average of 16 to 18 carbon atoms.

1% of this ketone when added to a waxy oil of 30 F. pour point reduced the same to +5 F. while 3% produced the same reduction.

This ketone was then recondensed with an equal quantity of ethylene dichloride to 150 of the ketone at refluxing temperature for 3 hours, using 10 gr. AlC13 and the product separated as before. 1% of this product reduced the pour point of the oil to -20 F. and 5% to below 30 F.

In another series of experiments the recondensation was repeated with different amounts of catalyst. When 30 and 50 grams of catalyst were used 1% of the product reduced the pour points of the oil from +30 to below 30 F.

Ewample VII 100 grams of naphthenyl ketone of naphthalene were prepared by the procedure shown in Example I using naphthenic oils (acid No. 215) instead of stearic acid. This ketone was then recondensed with an equal quantity of ethylene dichloride using 10 grams of A1013 at a reaction period of 3 hours. The product was separated as indicated in Example II and 82 grams were obtained. It was deep green and viscous.

1% of this product in the oil having an origina1 pour point of 30 F. produced a depression to 5 F., whereas 1% of the original naphthenyl ketone produced no reduction whatever. 5% of the recondensed product showed a pour point of 20 F. whereas 5% of the original showed none whatever.

The experiment was repeated using 20 grams of AlCls under the same conditions. 1% and 5% respectively in the waxy oil gave pour points of F. and -15 F. respectively.

Example VIII A naphthenyl ketone of benzene was produced and 100 grams were recondensed with 100 grams of ethylene dichloride using 7 grams of A1C13 for 3 hours. The product was finished as before and in the waxy oil showed a depression in pour point from 30 F. to l5 F., whereas the ketone in 5% concentration showed a depression from +30 F. to +15 F.

In the appended claims the word aroma-tic is intended to include simple carbocyclic and heterocyclic radicals as well as partially, but not completely, saturated hydroaromatic derivatives thereof.

' application is a continuation-impart of application Serial No. 248,234, filedDecember 29, 1938.

The present invention is not to be limited to any theory of the mechanism of the process nor to any particular reagents, catalyst and the like, but only to the following claims in which it is desired to claim all novelty inherent in the invention.

Iclaim:

1. A product obtained as distillation residue upon distilling to 600 F. a condensation product of a'keton'e having anaromatic group andanal-kyl radical of at least six carbon atoms with a dihalo aliphatic hydrocarbon compound having not more than 5 carbon atoms.

2. Product according to claim 1 in which the dihalo compound is an aliphatic chlorine compound containing from 1 to 5 carbon atoms.

3. Product according to claim 1 in which the dihalo aliphatic hydrocarbon is ethylene dichloride.

4. Product according to claim 1 in which the aromatic group of the ketone is a carbo-cyclic radical.

5. Product according to claim 1 in which the aromatic radical of the ketone is an aromatic radical.

6. Product according to claim 1 in which the aromatic radical is a naphthyl group.

7. An oil-soluble viscous residue obtained by distilling to 600 F. a condensation product, substantially non-volatile at temperatures up to about 600 F., of a ketone having the general formula RCOR, in which R is an aryl group and R is an alkyl group having more than 5 carbon atoms, with a halogenated hydrocarbon having the general formula (CH2) nXZ, in which X is a halogen and n is 1-5.

8. A viscous residue obtained by the steam distillation to 600 F. of a Frledel-Crafts condensation product of phenyl heptadecyl ketone with ethylene dichloride, said residue being soluble in mineral oil, substantially non-volatile at temperatures up to about 600 F. and having the property of lowering the pour point of waxy mineral lubricating oils when added thereto in small amounts.

9. A product obtained as distillation residue upon distilling to 600 F. a condensation product of a ketone having the general formula RCOR', in which R is a phenolic radical and R is an alkyl group having at least 5 carbon atoms, with a dichlor aliphatic hydrocarbon having 1-5 carbon atoms.

10. The process which comprises condensing a ketone containing an aromatic radical and an aliphatic radical of at least 6 carbon atoms with a dihalo hydrocarbon compound of l-5 carbon atoms, by means of a Friedel-Crafts catalyst, and distilling the product to 600 F.

11. The process which comprises condensing an aryl alkyl ketone having an alkyl group of at least 6 carbon atoms with a dichlor aliphatic hydrocarbon of 1-5 carbon atoms, by means of aluminum chloride at a temperature between about room temperature and about F., hydrolyzing the aluminum chloride catalyst and subjecting the condensation product to distillation to obtain as distillation residue a high molecular weight condensation product soluble in mineral oil.

12. The process of preparing wax-modifying compounds which comprises condensing about equal weights of a ketone having the general phenyl heptadecyl'ketone with ethylene dichloride in thepresence of aluminum chloride at a temperature between the approximate limits of room temperature and about 150 F., hydrolyzing and removing the aluminum chloride and subecung' the condensation products to fire and steam distillation to atemperature of about 600? F. toobt'ain'as distillation residue a high molecrular weight condensation product soluble in 'min- I eral oil and having pour-depressing properties when added to waxy mineral lubricating oils in small amounts. v V

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